On the Infinite is one of Bruno’s most insightful cosmological works. Written in 1584, it argues for a boundless, infinite universe, containing innumerable planets, all of which are inhabited. This was a revolutionary idea for the day, opposed to the traditional Aristotelian model of a unique Earth-centered system, encapsulated within a set of planet-bearing crystalline spheres, and surrounded by an outermost sphere of fixed stars.Bruno’s ideas and struggle with the Church authorities were recently featured on an episode of Cosmos, and excerpts from the book

Bruno wrote De Umbris in such a way as to give the reader a large selection of potential structures to use for a memory palace. Instead of a real, physical structure, one is encouraged to imagine structures and places. One could also use a poem or a book (Ovid’s Metamorphoses, as Bruno does), inserting things to be remembered in every scene. All of the lists of images in the book are designed to be used both as places (subjecta) and as memorable images (adjecta). The Zodiac, the constellations in the night sky (actual or fabricated), the decans associated with the Zodiac, or a diagram associated with a person, the parts of the body, or any other well-known system can be used.

The prefatory dialogue uses a number of the principles of making memorable images: we are more likely to remember an argument or what others have said, we’re more likely to remember caricatures (the other, disparaged memory experts), and we’re even meant to remember the advice tfor remmebering things the other experts give us in the dialogue.

Marsilio Ficino, in his Da Vita Libri Tres, gives examples of Egypitan magic. In one, taken from the Asclepius of Plato, the Egyptians supposedly called down celestial spirits into their statues that would then speak to their priests. Roger Bacon supposedly had a bronze head that could speak to him, either magically or through some kind of mechanical device.

Bruno implies that this idea can be applied more effectively inwardly. So, the memory artist is able to call up the image of Plato, who can speak the philosopher’s writings out loud to the person doing the imagining. In contemporary times, Hilary Mantel describes using this technique , as told to her by another author, to write The Giant, O’Brien based on conversations with the giant, who she visualized sitting in a chair in the room with her. Carl Jung referred to this technique as active imagination, and composed his Red Book based on a series of visions created by this method.

Ficino also described methods for counteracting depression (melancholy) and fatigue brought on by excessive study. The cures included counteracting the “influcence of Saturn”, thought to produce melancholy, by placing objects rich with “Solar”, “Jovian” and “Venerial” influence around the house and person. Actions like drinking cheerful young women’s breast milk mixed with honey and rose water would add to the amount of influence from Venus (the young women, the roses) and the Sun (the honey). Sitting outside in a garden, surrounded by daisies and other flowers sacred to the beneficent planets would also work. Surrounding onesself with bright, shiny metal objects or jewels inscribed with the right planetary symbols was also thought to counteract baneful influences. Now, we would say that elderly, depressed scholars would be cheered by getting outside in the sunshine, sitting in the garden with a pretty young woman and some nice gold baubles while drinking a pleasant drink. We would believe this came not from planetary, but rather psychological causes.

Bruno would likewise say that the best place to put a beneficial image is inside the memory artist’s palace. If you are depressed, place the image of the sun inwardly. Think about pretty girls and sitting in your garden, even if you are, as Bruno was, in the hands of the Inquisition. If you have a bad horoscope, place a detailed image of that horoscope inwardly and then change it to a better one. If you’re a real magician, who knows, maybe you can cahange your fate. If your image and your changes are convincing enough, maybe the universe will believe them, and conform to them.

The well educated, the nobles, the lawyers, and the clerics were brought before courts and judges to answer for the crime of sorcery, and they all answered with the same defense: I am a philosopher.

Apollonius of Tyana, who lived in the first century AD, came before one of Nero’s senior judges on the charge of sorcery because, it was claimed, he had foreseen and possibly cured the city through magic. Apollonius replied that he had in fact predicted the plague, because he was able to better understand the natural signs: in other words, through application of natural philosophy. The plague had been alleviated by the action of the god-hero Heracles, and that Apollonius had propitiated the god with a honey cake, rather than a blood sacrifice as a sorcerer would have done.(1) If I have remarkable abilities, it is not because I’m practicing the kind of magic you’re thinking of (the illegal kind), it’s because I’m so clever and learned about the ways of the world that I know what’s happening and the right thing to do about it. The magistrate ultimately found in Apollonius’s favor. Once you’ve distinguished whatever it is that you’re doing from the kind of magic the church and state authorities are concerned with, you’re relatively safe.

Giordano Bruno, in his essay On Magic (2), sets out ten commonly used definitions of magic and magicians. Bruno speaks approvingly of the older (philosophy-centric) definitions, and promotes the use of divine (religious), natural and mathematical magic, while denigrating both the practitioners and persecutors of the less savory types of magic as foolish. The magician, says Bruno, should just be a philosopher with “the power to act” and a strong knowledge of the natural and metaphysical worlds. This is in line with the ideal of the Renaissance magus as a learned man, skilled in many arts and in tune with the powers of the universe.

The presence of magical material in De Umbris should be understood in this context. In one sense, the presence of Neoplatonic, Hermetic and astrological material in this volume is clearly magical in nature, in the sense that this was seen as particularly effective philosophical material by Bruno and his audience; it is the best theory of physics and metaphysics available at the time, according to the cognoscenti of the time. Using it is also a sign that the author is part of the smart group. Hermetic, Platonic and Neoplatonic material, as originally translated by Marsilio Ficino and others some decades before, was still seen as “new knowledge”, balancing the existing Aristote-centric corpus of knowledge taught at the leading universities of the day, and which would lead the reader to new insights and capabilities. If Bruno had been writing in the present day, he might have included material on neuroscience and quantum mechanics as part of a pop science book; it is in the book to show that Bruno’s Art of Memory is based on the new, very old learning. Third, the material is included because it is interesting and slightly daring; it is an act of marketing, as if Bruno were to begin his mathematical astronomy lessons by putting on a pointy hat covered in stars, and stating that his students were about to learn some very secret, very sacred information. “You aren’t doing algebra, you’re doing ‘magical operations of the highest order’.”

Bruno, Giordano “On Magic”, in Giordano Bruno: Cause, Principle and Unity: And Essays on Magic. (1998) edited and translated by Blackwell, Richard, de Lucca, Robert, and Ingegno, Alfonso. Cambridge Texts in the History of Philosophy

In Western esoteric and mystical traditions, the circle represents a at least three classes of things: spiritual, spatial, temporal.

First, perfect things: God, the whole cosmos, the orbits of the planets (pre-Kepler). The trinity is represented in the circle as Father (center), Son (circumference) and Holy Spirit (the radii). In the formulation of Nicholas of Cusa that Bruno would have read, God is a circle of infinite circumference whose center is everywhere. It also represents the soul, as made in the image of God.

Next, circles represent spatial completeness: the world, whether as a globe or as the line of the horizon. Theaters, as in Shakespeare’s Globe, are model worlds. Circles in magical rituals were used to mark off areas of control, containment and separation: boundaries to protect the magician and contain the effects of the ritual.

Third, temporal cycles, ritual time: the clock face, the calendar, the movement of the Sun through the Zodiac. The Prague astrological clock (The Orloj) used as the background of this page, and on the cover of this edition, shows multiple time schemes as well as the positions of the run, moon and Zodiac.

Ramon Llull

Bruno combined the Greco-Roman memory palace technique with the use of lettered and compartmentalized wheels. The use of nested combinatoric wheels derived from Catalan mystic Ramon Lull, who used similar wheels as part of a logical system and art of memory, the Great Art (Ars Magna). Llull’s system combined a list of ten attributes of God, such as Beauty or Goodness, to develop propositions in support of theological or philosophical arguments. The arguments and attributes were demonstrated as existing at all levels of the Great Chain of Being (God, Angels, Humans, Animals, Plants and Matter) in various guises. Llull also used this system as the basis of a theological tool for showing the unity of Christian, Jewish, Muslim, and Pagan thinkers, with an eye toward converting others to Christianity.

Volvelles

Bruno had read a number of Llull’s works, and refers to Llull as one of the line of great memory artists in the prefatory dialogue to De Umbris, but he had an additional source for the kind of circular diagrams he uses here: the paper machines called volvelles. Bruno was many things to many people, but we are certain that he was a professor of astronomy and geometry, a highly popular lecturer at several of Europe’s largest universities at the time. Volvelles were teaching and demonstration apparatuses in common use at the time. Bruno would likely have used paper versions of astrolabes and other astronomical equipment for demonstration purposes during his lectures on Sacrobosco’s On the Sphere, the standard textbook at the time. We know that he was hired on several occasions to deliver lectures on astronomy and mathematics, that he published a commentary on this work, and named On the Shadows of Ideas on yet another (magical) commentary on Sacrobosco by De Cecco.

Cipher Wheels

Leon Battista Alberti published a text, On Ciphers in the mid-15th century, which included the use of a double wheel for encoding substitution ciphers, with the outer wheel fixed and the inner wheel moveable, as well as a system for enciphering a code of predetermined phrases or images.

Bossy’s Giordano Bruno and the Embassy Affair hypothesizes that Bruno worked as a spy while living in the household of the French Ambassador to the court of Queen Elizabeth I of England. While the evidence is somewhat tenuous, the application of Alberti cipher wheels to encipherment, and their existence in Bruno’s work is noteworthy. The memory palace technique itself would be extremely handy for someone carrying out secret missions as well. The possibility that the “magical” material in Bruno’s work is partially a cover for enciphering is also interesting in light of previous discoveries of secret codes embedded in the Steganographia and Polygraphia of Trithemius, which purport to be magical texts.

Za’irja

David Link points out that Llull probably got the idea for his combinatoric wheels from an Arabic divinatory device called a za’irja. This paper device appears to have been in widespread use among traders in the 13th century. What is interesting about the device is that, as with Trithemius’ books, its surface function or “cover” was magical, while the underlying functions may have been related to accounting and mathematical calculation. It is also curious that the za’irja Link references in his paper bear a surprising resemblance to a large diagram that Frances Yates constructed in her book The Art of Memory that combines all of the lists in On the Shadows of Ideas into one massive set of concentric wheels. Again, this seems to be another eyebrow-raising coincidence, as I have no evidence that Yates was aware of za’irja; Bruno never explicitly referenced them, nor did he lay out the concept of the giant Yates wheel in On the Shadows.